Scotland's justice secretary today labelled as "ludicrous" Westminster's claim that a prisoner exchange agreement with Libya did not cover the Lockerbie bomber.

Kenny MacAskill poured scorn on Downing Street's insistence that the memorandum of understanding, signed last week during a trip by Tony Blair to Libya, did not apply to Abdelbaset Ali Mohmed al Megrahi.

First Minister Alex Salmond has protested to the Prime Minister over the agreement, which he suggested could lead to the Lockerbie bomber being transferred from Scotland to his homeland.

Mr MacAskill told BBC Radio's Good Morning Scotland that Westminster's handling of the affair was "at minimum, discourteous to the First Minister and the Scottish Parliament".

The agreement has sparked the first major row between the Government and the minority SNP administration north of the border, and triggered an emergency statement yesterday at Holyrood from the First Minister.

Mr MacAskill continued: "There's no mention of al Megrahi (in the memorandum) but we have many people in our prisons...but we have only one Libyan national in our prisons.

"So when we're talking about the transfer of Libyan prisoners they are not secreted in Barlinnie, Saughton, Perth or anywhere else.

"We have only one Libyan national in custody and when we talk about the transfer of prisoners, frankly it is ludicrous to suggest that we are talking in a context other than this major atrocity that was perpetrated on Scottish soil and which was dealt with by a Scottish court and with a sentence provided by Scottish judges."

Tony Blair was earlier accused of striking a secret deal with Libya over the Lockerbie bomber being returned home.

The Prime Minister was plunged into an extraordinary row over a "memorandum of understanding" on prisoner transfers he agreed with Colonel Gaddafi last month.

Families of some of the 270 people killed in the 1988 bombing reacted with anguish to the prospect of Abdelbaset Ali Mohmed al-Megrahi, jailed for life in 2001, leaving his Scottish jail to serve his sentence at home.

The possibility was raised by Scotland's new first minister, Alex Salmond, in an emergency statement at Holyrood. He said the deal Mr Blair signed in Tripoli on May 29 specifically covered prisoner transfer.

Mr Salmond said the Scottish government had not been told in advance of the deal. This was "clearly unacceptable".

Mr Blair visited Libya as part of a globetrotting African tour intended to establish his legacy. He applauded Gaddafi for dismantling his weapons of mass destruction.

But the father of one of the Lockerbie victims said: "This is a dirty deal. Is this Tony Blair's goodbye, best farewell to Gaddafi?"

Downing Street moved quickly to insist there was no prospect of Megrahi going home. Mr Blair's spokesman insisted: "We are discussing a memorandum of understanding with Libya but that would not affect this case.

"We do not regard Megrahi as covered by anything that would flow from this. We made that very clear in the talks over there."

But the text of the agreement, released by the Foreign Office, does not include or exclude any individual. Instead, it notes the "desire of both sides to strengthen judicial cooperation" and says negotiations will soon start on extradition and prisoner transfer.

Mr Blair first met Gaddafi in 2004 after the former godfather of world terrorism finally accepted blame for Lockerbie and paid more than £2billion compensation.

News of the deal also sparked speculation that it could pave the way for the killer of Yvonne Fletcher, the policewoman shot dead from inside the Libyan Embassy in 1984, to be sent to London to face justice.

Scotland Yard officers are in Libya and are believed to have made "significant progress" in identifying the Gaddafi loyalist who shot the unarmed officer in the stomach. All the suspects had to be allowed home after claiming diplomatic immunity.

Megrahi's case is currently being reviewed by the Scottish Criminal Cases Review Commission, which could send it

"Does the Prime Minister of the United Kingdom have the legal and constitutional authority to release a person serving a prison sentence for life in a Scottish jail?

"I am deeply alarmed by the actions of the Prime Minister, which on a practical, political and legal basis are frankly shoddy and shabby conduct."

American Dan Cohen, 70, whose only daughter Theodora, 20, was on Pan Am flight 103, said: "This is a dirty deal. Is this Tony Blair's goodbye, best farewell to Gaddafi?

"This is horrible, absolutely horrible. I can't see any conceivable justification for it.

"As far as justice is concerned, it's an absolute travesty. I have nothing but the deepest contempt for any official who signed up to this deal, absolute contempt. I hope Scottish law prevails."

Dr Jim Swire, whose daughter Flora was also killed in the disaster, said: "What about the relatives, for God's sake?

"The first we have heard about this is from Alex Salmond. I'm furious. What's this man Blair negotiating about Megrahi without mentioning a word to us?

"What kind of Prime Minister does this? I'm actually livid about it, it's an atrocious way for a Prime Minister to behave."

But Dr Swire added: "I personally don't believe for a moment that he (Megrahi) is guilty as charged and I know from sources that he is pining for his family and children.

"From a human point of view I think it would be an excellent thing if he was sent to Libya.

"What's important is to get to the bottom of who did murder our loved ones."

A senior Foreign Office source said the Libyans were "talking up" the prospect of Megrahi being returned.

He said: "There will be various elements and prisoner transfer might be one of them. The Libyans think this is their best chance of getting Megrahi back but we don't share that interpretation."

Although Megrahi's appeal in March 2002 was dismissed, there has been some disquiet over his conviction. It was described by an independent UN-appointed observer at the trial as a "spectacular miscarriage of justice".

In October 2005, it was reported that Britain, the U.S. and Libya were negotiating the transfer of Megrahi to a prison in his home country on the condition he drops any appeal against conviction.

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